Especially in the case of twin clutch transmissions or parallel gearboxes, the clutches are constructed in such an advantageous manner that, when their actuators fail, they open automatically. Even for referencing the position of the clutch actuating system, one proceeds preferably on the assumption of an auto-opening clutch system, where, for example, upon deactivating the actuator, an opening position, which is defined by a stop abutment, is actuated automatically. This opening position is used for referencing an incremental sensor, which serves as the position sensor.